EcotaxDEEE choose to have only one line or display each ecotax to the specific line

[BenjaminFlr]

Is your feature request related to a problem? Please describe.
Some customer may want to have a detailed ecotax line for each line/product, because it allows their customer to bill the ecotax too.

Describe the solution you'd like
It could be interesting to add a new line in the order/invoice/propal/... linked to the related one which would be passed as $fk_parent when adding the product.

Also, it would add the necessity to calculate the total for ecotax lines and display it in the tableau_tot. This feature could be enabled or not from the module menu.